[Seasonal characteristics of the effectiveness of vitamin E and sodium selenate in tetracycline-induced liver damage].

The seasonal characteristics of the efficacy of vitamin E and sodium selenite in tetracycline affections of the liver were studied on 128 noninbred male albino rats. It was shown that in comparison to vitamin E sodium selenite more actively retarded activation of lipid peroxidation in the liver and activation of alanine aminotransferase and alkaline phosphatase in the blood serum in autumn and winter. A more pronounced inhibition of the increased levels of the dienic conjugates and alanine aminotransferase was observed in spring and summer and malonic dialdehyde and aspartate aminotransferase in summer by tocopherol acetate as compared to sodium selenite. The level of the thiol-disulfide equilibrium on the separate use of the drugs in spring and summer was higher than the control one. However, it did not reach the control level in autumn and winter. The combined use of sodium selenite and vitamin E prevented the toxic effect of tetracycline on the liver in autumn, spring and summer. Still, in the winter no such prevention was observed. The mechanisms of the seasonal differences in the tetracycline effect on the liver and the efficacy of the antioxidants in such affections are discussed.